Understanding Different Types of Curves

In surveying and civil engineering, curves are used to connect straight sections of roads, railways, or pipelines smoothly. There are several types of curves, each defined by its geometry and the arrangement of its circular arcs.

Reverse Curve Definition

Let's look at the definition provided in the question: a curve consisting of two circular arcs that share a common tangent point, known as the point of reverse curvature (PRC). The key characteristics are:

• It has two circular arcs.
• The radii of these arcs can be the same or different.
• The centers of the two arcs are located on different sides of the common tangent at the PRC. This arrangement causes the curve to change direction (reverse) at the common tangent point.

Analyzing the Options

Let's consider how each option fits the description:

1. Reverse curve: As discussed above, a reverse curve is defined by two circular arcs, possibly different radii, and centers on opposite sides of the common tangent. This definition perfectly matches the question.

2. Differential curve: This term is not standard terminology for types of horizontal curves in surveying.

3. Compound curve: A compound curve consists of two or more circular arcs tangent to each other, but the centers of these arcs are on the same side of their common tangent. This is different from the description in the question where centers are on "different sides".

4. Simple curve: A simple curve is a single circular arc connecting two tangents. It does not consist of two arcs.

Comparing Curve Types

Here's a brief comparison of reverse and compound curves:

• Reverse Curve: Two arcs, centers on different sides of the common tangent. Changes direction.
• Compound Curve: Two or more arcs, centers on the same side of the common tangent. Continues in the same general direction but with changing curvature.

Based on the definition provided and the analysis of the options, the curve described is a reverse curve because it consists of two circular arcs with centers on different sides of the common tangent.